Full Version: Macarthur HAT with Daisy and GPS on UART0?
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Hello, first time poster here.  I have been working on configuring my OpenPlotter hardware and I currently have my GPS connected through the RPi4 UART0 pins.  If I attach a MacArthur HAT and dAISy hat, will I have to remove the GPS from the port?  It looks like MacArthur uses all 5 of the HW UART locations, so will I have to replace my current GPS with a USB unit?

Thanks everyone for your time in helping the community to make use of these awesome tools.
Yes, UART interfaces can not be shared. Your options are USB or another UART interface. Look at the "Header pinout" chapter for more info:
There's also a feature of the dAISy HAT, to configure its Serial 2 port as an input that forwards any NMEA data to the Pi. With that, you could wire up the GPS module on the dAISy HAT and get the GPS data from the same port as AIS.

I only tried this with OpenCPN, but SignalK is probably also capable of handling the mixed data stream.
Sorry I forgot that. Wait... it could be another way. Technically you could also use UART2 in Raspberry 4 (GPIO 0 and GPIO 1) or UART1 in Raspberry 5 (GPIO 0 and GPIO 1) because they are not used by the MacArthur HAT, it should work as long as you do not connect any HAT with EEPROM, let me do some tests...